My 97SE has the "base model" hvac controls with the 4-position **** to control fan speed. Going from left to right, let'* call the positions 1,2,3,and 4. For several months now, something is wrong with mine, where 1,2,and 4 work normally, but 3 is the same blower speed as 4, except for a very little tiny zone almost between 2 and 3, where I get what should be the 3 fan speed. The click points have not moved, the switch still click centers in each position, but when centered on 3, I get the same high fan speed as 4.

Ideas? My only experience with these things is with blower motor resistors having one or more of their elements burning up, which causes one or more positions to have no fan speed. That doesn't seem to be the case. I have no idea what might be causing this.